The aim of the Principal Research Core (PRC) is to conceptualize, design and advance the research program of the ACISR aimed to reduce the burden of depression and disability of older persons. Accordingly, the PRC will promote clinically meaningful research and translate its findings, along with other breakthroughs of our field, into everyday practice so as to increase the number and effectiveness of evidence-based practice guidelines in community care. The PRC relies on: 1. a group of investigators with complementary expertise, including biological and clinical research, primary care studies, sociology, and statistical methodology; 2. an organization that rapidly and efficiently translates biological and psychosocial findings into intervention studies; 3. a track record of independently funded studies (16 newly funded in the past year) ranging from projects that build the scientific foundation for interventions studies, to efficacy, effectiveness, and practice research; 4. experience in career development of investigators (three NIMH K Awards received in the past year and one is under review); and 5. working research partnerships with the County Department of Senior Programs and Services, the County Department of Mental Health, community based primary care practices, rehabilitation hospitals; and home health care agencies. The process of research development and coordination relies on the PRC Executive Committee to identify gaps in our research portfolio as well as strengths of our Center (research expertise and availability of data) and develop initiatives to address these gaps. The six Pilots presented in this application exemplify this process. The PRC works closely with the Research Methods Core (RMC); it provides to the RMC a stimulus and data for its methodological studies, while it incorporates the RMC innovations in the designs of substantive studies. Finally, jointly with the Research Development Network Core (RDNC) and its community partners, the PRC conceptualizes and studies programs of care for the depressed elders in our community.